The present invention relates to wet treatment of photographic materials, such as sheets or webs of photographic film or paper.
Conventional apparatus for wet treatment of photographic material have treating chambers through which the photographic material advances along a horizontal path. Pairs of advancing rollers are provided at the upstream and downstream ends of the chamber and the treating liquid is pumped into the interior of the chamber. As a rule, the chamber is a plenum chamber into which the treating liquid is admitted at a high speed through small openings. A drawback of such prior art apparatus is that even slight fluctuations in the quantities of liquid pumped per unit of time will result in inadequate liquid pressure so that the photographic material will undergo a non-uniform treatment.
According to another prior proposal, the treating chamber is subdivided into a main chamber and two end chambers each of which accommodates one of the pairs of advancing rollers. The dividers between the chambers have portions which are shaped to cooperate with the advancing rollers so as to make the main chamber as fluidtight as possible. This causes the liquid bath in the main chamber to rise to a level above the plane of the advancing photographic material. Although this concept is basically advantageous, it has been found that the apparatus is too complicated. Also, the treating liquid is admitted at the bottom of the main chamber which induces a liquid flow that is different with reference to the two major surfaces of the photographic material. This can result in non-uniform developing, especially of X-ray films.